CVE-2026-116366: Unauthenticated RCE vulnerability against ClickHouse Server

Awaiting analysis

AliasesDEBIAN-CVE-2026-116366

Published 30-10-2026Last modified 30-10-2026

Vulnerability summary

CVE-2026-116366 is a critical (CVSS 9.5) Integer Overflow or Wraparound vulnerability in clickhouse. EPSS estimates a 0.96% chance of exploitation in the next 30 days, higher than 61.6% of scored vulnerabilities.

Priority

Prioritisesevere

Severe, CVSS 9.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?

CVSS score

9.5/10

010

Critical · v4.0 (CVE.org)

EPSS score

0.96%

0%100%

Low · Change unavailable

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits0No public exploits recorded

Timeline

30-10-2026
PublishedVulnerability first disclosed.
30-10-2026
Last modifiedVulnerability information updated.

Description

An issue has been discovered in ClickHouse Server that, under certain conditions, could allow an unauthenticated user with network access to execute arbitrary code on the ClickHouse Server.

CVSS metrics

3 scores · 3 sources · 1 version

v4.09.5

EPSS trend

Probability

0.96%

Chance of exploitation in the next 30 days

Percentile

62%

Versus all other CVEs

30-day change

Change unavailable

31-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

CWE-190Integer Overflow or WraparoundThe product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Clickhouse2 products

clickhouse≥ 26.3, < 26.3.62.3-lts | ≥ 26.8, < 26.8.36.3-lts | ≥ 26.9, < 26.9.27.3-stable | ≥ 26.10, < 26.10.3.7-stable
clickhouse cloud≥ 25.12, < 25.12.1.1713 | ≥ 26.2, < 26.2.1.835 | ≥ 26.4, < 26.4.1.2704 | ≥ 26.6, < 26.6.1.2439 | ≥ 26.8, < 26.8.1.597 | ≥ 26.10, < 26.10.2.84

Debian1 product

clickhouseAll versions (No fix recorded)

2 vendors · 3 products

References

3 links